非,底面是圆,中心角为 $60^\circ$,即两半径与弦(顶点到圆周两端)所成角是 $60^\circ$。


Is This the Real CS: Source Font?
Stop Ruining Your Razor Game—Boost FPS With This Hidden Setting
The Secret Sand Dumper Truck That Builds Massive Bases
Why 90% of Players Fail at Cut the Rope Play Free—Can You Beat the Odds?
Unlock the Ultimate Red, White, and Blue Rice Krispie Treat!
Demon Slayer Hinokami Chronicles 2 Trophy Guide: Unlock the Secret Achievements
Game Over: The One Dip Every Gamer Is Crazed For
The Forbidden Uno Rule That Causes Total Chaos at Every Party
Level Up Your Game With This Southern Living Potato Soup
What Happens When You Play Uno With Celebrities? The Results Are Hilarious